1. Field of the Invention
Implementations described herein relate generally to on-line advertisements and, more particularly, to using estimated ad qualities for filtering, ranking and promoting on-line advertisements.
2. Description of Related Art
On-line advertising systems host advertisements that may advertise various services and/or products. Such advertisements may be presented to users accessing documents hosted by the advertising system, or to users issuing search queries for searching a corpus of documents. An advertisement may include a “creative,” which includes text, graphics and/or images associated with the advertised service and/or product. The advertisement may further include a link to an ad “landing document” which contains further details about the advertised service(s) and/or product(s). When a particular creative appears to be of interest to a user, the user may select (or click) the creative, and the associated link causes a user's web browser to visit the “landing document” associated with the creative and associated link. This selection of an advertising creative and associated link by a user is referred to hereinafter as a “click.”
On-line advertising systems often track ad clicks for billing and other purposes. One non-billing purpose for tracking ad clicks is to attempt to ascertain advertisement quality. The click through rate (CTR) is a measure used to determine advertisement quality. CTR represents the fraction of times a given ad gets “clicked” on when a given advertisement is presented to users. The CTR of an advertisement, however, is an imperfect measure of advertisement quality since it focuses on the advertisement creative rather than the object of that advertisement, which is the landing document. A user needs to click on an advertisement in order to determine if an advertisement is good or bad and, therefore, the occurrence/non-occurrence of a click is insufficient to determine the quality of an advertisement. Some advertisements receive many clicks because they have a good creative, but the landing document is completely unsatisfying, or irrelevant, to the user. Other advertisements receive very few clicks (e.g., due to the advertisement creative being poor), but every click leads to a satisfied user. Existing determinations of CTR associated with on-line advertisements, thus, provide imperfect measures of advertisement quality.
Furthermore, in existing on-line advertising systems, the advertisements that are displayed to users, and the ordering of the advertisements displayed to the users, are based solely on an advertisement's CTR and the max “cost per click” (CPC) that an advertiser is willing to bid to have its advertisement shown. The CPC is the amount that an advertiser is willing to pay an advertisement publisher and is based on a number of selections (e.g., clicks) that a specific advertisement receives. To the extent that CTR is being used as a surrogate for advertisement quality, it is insufficient for the reasons already set forth. Existing mechanisms for determining which advertisements to display, and for ranking the advertisements, thus, use an imperfect measure of advertisement quality that may not provide the highest quality advertisements to users.